Sensitivity of the improved Dutch tube diffusion test for detection of antimicrobial residues in Kenyan Milk.

The sensitivity of the improved two-tube test for detection of antimicrobial residues in Kenyan milk was investigated by comparison with the commercial Delvo test SP. Suspect positive milk samples (n =244) from five milk collection centers, were analyzed with the improved two-tube and the commercial Delvo SP test as per manufacturer, weekly over a ten-week period. The 't' test statistic was utilised based on the hypothesis: H0: Ud = 0 (U2 - U1 = Ud) and Ha: Ud > 0 (one-sided test) to analyse the results. The t calculated was compared to the tabulated t value at p = 0.05 for ten degrees of freedom. The results suggest that the improved two-tube test has some improved effect on the sensitivity for antimicrobials residues in comparison to the commercial Delvo test. Utilizing the improved two-tube test could lead to an improvement in sensitivity for antimicrobial residues. The Journal of Food Technology in Africa Volume 6 Number 1 (January-March 2001), pp. 5-7 KEY WORDS: milk, antimicrobial residues, Bacillus stearothermophilus var. calidolactis. Maximum residual limits (MRLs), Improved two-tube test.